Solid-state imaging devices such as a CCD image sensor and a CMOS image sensor are used in, for example, a digital camera, a video camera and a surveillance camera for various purposes. To address a decrease in pixel size, some of the solid-state imaging devices employ a backside illumination structure that is advantageous for securing an amount of light incident upon a photodiode. A backside illumination solid-state imaging device can be improved in sensitivity and image quality because it excludes an optical obstacle such as a metal interconnection between a light-receiving area and microlenses.
The backside illumination solid-state imaging device comprises a pixel area including light-receiving elements and a peripheral circuit. The peripheral circuit is arranged like, for example, a ring around the pixel area and include a logic circuit and an analog circuit. If a peripheral circuit area is decreased in width to miniaturize the device, it is lengthened, which makes it difficult to provide lines, especially power lines in the peripheral circuit. Thus, the power lines increase in resistance and the power drop of the device becomes great, with the result that the power of the device becomes unstable.